111838781 has 2 divisors, whose sum is σ = 111838782. Its totient is φ = 111838780.

The previous prime is 111838763. The next prime is 111838787. The reversal of 111838781 is 187838111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58767556 + 53071225 = 7666^2 + 7285^2 .

It is a cyclic number.

It is not a de Polignac number, because 111838781 - 2¹⁰ = 111837757 is a prime.

It is a super-2 number, since 2×111838781² = 25015825871131922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111838787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55919390 + 55919391.

It is an arithmetic number, because the mean of its divisors is an integer number (55919391).

Almost surely, 2^111838781 is an apocalyptic number.

It is an amenable number.

111838781 is a deficient number, since it is larger than the sum of its proper divisors (1).

111838781 is an equidigital number, since it uses as much as digits as its factorization.

111838781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10752, while the sum is 38.

The square root of 111838781 is about 10575.3856194467. The cubic root of 111838781 is about 481.7970556246.

The spelling of 111838781 in words is "one hundred eleven million, eight hundred thirty-eight thousand, seven hundred eighty-one".